


Whine

by kittenofdoomage



Category: Supernatural
Genre: Alpha!Dean, Alpha/Beta/Omega Dynamics, Alpha/Omega, Anal Sex, Knotting, M/M, NSFW, Omega!Castiel, Sex, Sex under influence, Smut, omega!cas, wing!kink
Language: English
Status: Completed
Published: 2017-02-11
Updated: 2017-02-11
Packaged: 2018-09-23 13:38:10
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,903
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9659687
Author URL: https://archiveofourown.org/users/kittenofdoomage/pseuds/kittenofdoomage
Summary: Written for the SPN Smut Appreciation Day. This is my first ever exclusively Destiel fic. Circa end of S10. Rowena's spell has a different effect than intended, bringing out Castiel's latent Omega genetics. He needs his Alpha, and he needs him now.





	

‘Impetus bestiarum!’

The spell slammed into Castiel with the force of a thousand knives, sending him to his knees, the witch’s laughter echoing in his ears as she fled the building, and he clutched his head, agonising pain ripping through his vessel.

His insides were twisting as he writhed on the filthy floor, ancient instincts rising to the surface as he dug his nails into his hair, tugging hard at the short strands. Vaguely, he heard Crowley call for him, but all he could do was snarl in response.

A deep need pushed its way through everything else, and Castiel lifted his head, screaming in pain before collapsing into heavy pants, his fingers scrambling to loosen the tie around his neck. It relieved a little of the pressure, and he sucked in a lungful of air, unsure how to deal with the new reality around him.

‘Castiel.’ Crowley’s voice made him snap his head around, and the angel got to his feet, still breathing heavily, his skin flushed red and his vessel sweating profusely. ‘What the hell did she cast on you?’

Castiel winced, shaking his head, just about making Crowley’s words out around the rushing of his own blood in his ears. He couldn’t feel his grace to heal whatever Rowena had done, and the gnawing in the pit of his stomach grew closer as he stumbled towards the King Of Hell. Crowley tried to move away, but he was frozen to the spot, the witch’s magic rooting him firmly.

‘Castiel, you need to listen to me, she’s put a spell on you -’

‘Attack dog,’ Castiel growled. ‘She has used that spell before but… something is wrong.’

Crowley frowned, sniffing delicately. ‘I’ll say. You smell like an Omega.’ He raised an eyebrow. ‘Angel’s don’t tend to pick a gender, do they?’

Castiel shook his head, clutching at his stomach, groaning in pain. ‘They do not. My vessel, Jimmy Novak, was Omega.’

‘Did Jimmy have a mate?’

‘Amelia Novak. She’s dead.’

‘Oh.’

‘It is not of import. Jimmy’s soul no longer resides in this form.’ Castiel cried out again, almost dropping back to his knees in pain. Crowley tried to pull his legs forward, unsure of how to deal with the angel in this condition. ‘His soulmate was Amelia and she is gone.’

‘So who’s your soulmate?’ The demon questioned, and Castiel groaned, making Crowley roll his eyes in frustration. ‘Dean. Dean Winchester is your sodding soulmate. The amount of pussy footing you two do around each other, and  _ now _ look at the mess you’re in. Can you even fly?’

‘Why do you care?’ Castiel spat, clutching his midsection. After years of repression, everything inside him was churning, ever instinct and need that any Omega had, and everything in him wanted his Alpha.  _ Dean _ . If he’d been a normal human, he’d have taken the chance on the hunter years ago, but he’d never been normal, and he’d never had occasion.

Crowley tutted, shaking his head. ‘I’m stuck here, with you. And I’d rather not get jumped by a horny Omega, thank you. I’ve got my own.’

‘I need Dean -’ Cas ground out, hearing Crowley sigh. ‘Where did they… ‘ He looked up, closing his eyes, searching the planet as best he could with his grace tempered by the Omega instincts. Dean wasn’t far - he could feel the spark of his soul, so much brighter to him now. ‘I can feel him…’ He focused, and spread his wings, disappearing from the run down building, landing a few miles away, panting for breath. Everything in his body was stopping his powers, holding him back, but he knew he had to get to Dean.

Gathering everything he had, he spread his wings once more, willing himself to where he could sense his mate… and the darkness rising above him. All at once, the cloud surrounded him, pinning him down, and tearing at his wings, and Castiel screamed, reaching out to claw at the ground underneath him.

And then everything was black.

*****

Strong arms pulling him from the ground made him groan, Rowena’s spell awakening as soon as his consciousness returned. He whimpered at the rough touch, and the sensation of being dragged, but whatever had caught him, whatever blackness had seized him, he didn’t have the energy to fight back. His body ached and pined, and he muttered a mixture of Enochian and English as he tried to fight his way through the haze of darkness that coated his mind.

But it wasn’t a fight he was about to win, and he surrendered, allowing the arms that carried him to continue without resistance.

The second time he woke, it was to a much softer touch. He felt lighter, but the spell lingered on the edge of his consciousness, and he moaned under his breath, unwilling to open his eyes.

‘Cas?’

Sam. Sam had found him.

Reluctantly, Castiel cracked one eye open, finding himself in the bedroom he’d frequently used at the bunker. He had no knowledge of the time or date, and he could barely feel his grace. Everything that hounded his insides was a compacting need for his mate, and he knew wherever Sam was, Dean could not be far.

He opened his mouth, but all that came out was a wracked cough, and Sam was quick to reach for a glass of water at the bedside, offering it to him without hesitation. Castiel took it, sipping gingerly at the water, knocking his teeth on the edge of the glass as the coughing fit continued. 

‘Easy, easy,’ Sam whispered, smiling softly as he helped his friend to take a drink. ‘What the hell happened to you, man?’

Castiel sucked in a breath as the coughing subsided, taking a last sip of the water before giving the glass up to Sam’s hold. ‘Rowena… cast a spell on me.’ He shut his eyes as his insides clenched, his entire being calling for what it needed. ‘The attack dog spell... the same…’

‘The same one she used on those girls.’ Sam finished, watching as Cas lay back and closed his eyes again. He recognised what the angel was dealing with - he’d seen Jess go through it once or twice. It didn’t affect the Beta, but he’d known something was wrong the second Dean had recoiled from the simple sight of Castiel where they’d found him passed out and injured in the field near where Dean’s meeting with Death had gone down.

Sam had instantly sent Dean back to the car, keeping him focused on the task of getting home safely, whilst the younger Winchester dealt with the Omega in the back seat. Whilst he was unconscious, dealing with Dean’s reaction to him was easy; now he was awake, it would be much harder to keep the Alpha from the Omega that he’d held back from for so long.

‘Dean -’ Cas started, and Sam frowned, seeing sweat beginning to bead on the angel’s forehead.

‘He’s fine,’ Sam replied, his brow creasing further as Castiel groaned and gritted his teeth. ‘Don’t get me wrong, this would have been easier if you’d picked a different time to present -’

‘I’m not presenting,’ the angel replied, shaking his head, but not opening his eyes. ‘My vessel was always Omega. Angels do not have a gender or biological need to mate. The spell that the witch cast… it has made my… latent genetic need more prominent. I can feel it, changing me, preparing me -’

Sam baulked a little at that - it was one thing to know Castiel was an Omega and quite another to think of the way his body was changing, especially with the not-so-metaphorical Alpha in the building. He wasn’t sure whether to keep them apart until they found a counterspell to whatever mystical curse the angel was under, or to let it run it’s course.

A motel might be order for the latter suggestion.

He sucked in a breath, focusing on his friend. Castiel was sweating profusely now, his body twitching as he fought whatever battle was going on inside his body. ‘Castiel, I don’t know what to do here.’ Sam was suddenly glad he’d removed the majority of Cas’ clothing when he was unconscious. He didn’t doubt that the trench coat and shirt would have been uncomfortable in his current condition. ‘I don’t know what to do to fix this.’

‘I can fix it.’

Sam’s head snapped round, and Castiel’s eyes opened, both of them looking towards the door. Dean was leaning heavily on the door frame, his shirt half open as he stared at Castiel. The younger Winchester stood, placing himself between Dean and Cas, holding his hands up.

‘Dean, this might not be such a good idea,’ he started, but Dean pushed up off the wall, shaking his head. ‘You’re not thinking clearly -’

‘I can fix it,’ Dean insisted, stopping a few steps from his little brother, his green eyes softening. ‘Don’t think I’m in rut, Sam, I’m not. But Castiel is hurting, and I can  _ fix _ that.’ He stared at him earnestly, shaking his head again. ‘I’m the only one who can give him what he needs.’

‘What if it doesn’t fix the spell?’ Sam asked, softly, tilting his head to the side. ‘You can’t rush in like this -’

‘I’ve been researching for hours. He’s an Omega. He needs hi -  _ an _ Alpha. I’m the only one we got.’

Sam regarded his brother with worry, knowing the buried feelings he’d had for Cas for too long. He’d never acted on a single one, never  _ told _ his best friend that he was head over heels. He’d never assumed Castiel would feel the same way and he’d known from day one that angels didn’t share the same bond a mated human pair would.

But things had changed now.

‘What if it fixes it, and he goes back to how he was? Angels and humans… they don’t bond, Dean. That could  _ literally _ kill you.’

Dean was silent for a moment, considering his brother’s words, before sighing heavily. Castiel groaned on the bed, and Dean’s body tensed as the Omega scent grew stronger. ‘I’m gonna have to take that risk. It only  _ might _ kill me, but it definitely  _ will _ kill him.’

Sam hesitated, before nodding. ‘I’m trusting you with this, Dean. I hope it’s not a mistake.’

‘It’s not,’ Dean exhaled, his eyes going beyond Sam to the Omega on the bed. ‘You might wanna keep your cell on.’

‘I will. But I’m gonna find a bed somewhere else while you deal with this, okay? Not to be a prude but -’

Dean grinned, reconnecting his eyes with his brother’s. ‘Yeah, yeah, I got it. Get out of here, okay? I’ll call if there’s any problems.’ Sam gave him a curt nod, before moving out of his way, heading towards the door, pausing to look back as Dean walked towards the bed. Then he was gone, leaving the angel and hunter alone.

‘Dean?’ Cas looked up from the bed, watery blue eyes regarding the Alpha carefully. It was taking everything he had left to hold himself down, to not launch himself at the other man, and Dean was clearly having the same problem. His body shook as he watched him, his fingers trembling at his sides.

A moment passed, and Castiel thought Dean might leave, but then he sank down, sitting on the bed beside the ailing angel, reaching out to feel his forehead. ‘You’re burning up, Cas.’ His tone was gentle, and the angel almost swooned at the touch. ‘You’ve never been through this before, have you?’

‘My Omega traits were always controlled by my grace. Even when I was human, I never experienced this. The spell… it changed me.’ He shut his eyes for a second, before opening them, blue almost glowing as he stared at Dean. ‘Everything in me is crying out for an Alpha… for you, Dean.’

Dean nodded, but he didn’t move, save to remove his hand from Castiel’s forehead. ‘I know. I… I never took an Omega. Was always you, I guess.’ He sighed. ‘I didn’t want it to happen like this. But that’s what I get for ignoring it for so long.’

‘I can fight this,’ Castiel insisted. ‘If you don’t want to -’

‘No, I do. That’s the problem, Cas. I do this… I won’t hold back. It’s an all or nothin’ deal for me, and I don’t - I don’t know if I could put you through that. Being tied to me -’

Castiel’s fingers found his shirt sleeve, clasping it tightly. ‘Is all I ever wanted. You and I have shared much together, Dean. Fear kept us apart, and now, necessity warrants this.’

Dean smiled, locking his green eyes on Castiel’s. ‘So, you’re sayin’ we should make the best of a bad situation?’

The angel smiled right back, nodding, despite the pain wracking his body. ‘Yes. And I am glad it is you, Dean. To be bonded to you, would be a great honour.’ He grit his teeth as his stomach churned and cramps rolled through his midsection. ‘I do not understand why this hurts so much.’

The hunter leaned in, stroking Castiel’s hair back from his forehead, pressing his nose against his, inhaling deeply the scent that was uniquely Castiel, and entirely Omega. ‘Let me make it better.’ His lips brushed against the angel’s, and Cas sighed, opening his mouth to accept the caress. Dean moaned a little as his tongue pressed in, tasting the inside of the Omega’s mouth softly. Cas’ skin felt like a thousand degrees, and Dean pulled back, quickly removing his shirt, before pulling the covers off of the bed. ‘You’re burning up.’

‘Feel hot all over,’ Cas groaned, moving a little to make room for Dean on the bed. He was only wearing his long boxer shorts and he could only assume that Sam had removed his clothing whilst he was incapacitated. ‘Does it stop?’

‘It does,’ Dean assured him, pulling him close to claim his mouth again. Castiel whined against him, prompting Dean to push a little harder, thrusting his tongue against the other man’s as his hands ghosted over his bare torso. ‘Fuck, Cas, you smell so good.’

Cas mewled as Dean abandoned his mouth, moving his head to place wet kisses along his jaw and neck, blunt teeth nipping at the Omega’s sensitive skin and making his body tremble. Keeping his pace slow, Dean slid one hand down, under Cas’ boxers, finding him hard and swollen, tenting the material. ‘F-feels good,’ the angel stuttered, arching up into Dean’s touch. ‘I ache, Dean.’

‘I know what you need,’ the hunter replied, his questing fingers bypassing the angel’s straining erection to slip underneath his sac, finding his hole already dripping and open. ‘So fucking wet, baby,’ he muttered, sliding one finger between Cas’ cheeks, making the Omega yelp. ‘Feel good?’ The angel nodded, gasping for air as Dean pushed his finger into his ass, easily aided by the slick already there.

‘N-need more,’ Castiel whimpered, not even trying to stop the instinctive grind of his hips down onto Dean’s finger. Dean added a second, pressing his face into Cas’ neck to stifle the groan at feeling the wet, tight heat around his digits. ‘Dean -’

The Alpha growled against his skin, making Cas’ stomach do a funny flip flop motion. ‘Sam was right. I’m not gonna be able to do this without making you mine, Cas, and I can’t… I can’t lose you.’

‘You won’t lose me,’ Cas replied, his tone desperate as he rolled his hips, pushing more and more of Dean’s thick fingers into his body. ‘I will not leave you.’ Dean grunted, pulling his fingers away, swallowing the angel’s protests with a brutal kiss. ‘Dean -’ He moaned, the word muffled against his lips.

Dean pulled away, scooting off the edge of the bed again, looking down at Castiel as he got to his feet. The boxers the angel wore were almost soaked through, and the hunter groaned in need, unbuckling his pants. ‘Present for me, Omega. Show me that sweet little hole.’

Cas gasped, pushing up onto his knees, his shaking hands working to remove the boxers. Dean watched, removing his jeans and underwear, palming his thick cock as he watched the angel bend. His firm ass was in the air, slick coating his thighs, a fresh bloom of Omega scent flooding the room, and Dean groaned, closing his eyes to relish the sweet smell.

He wanted nothing more than to rush, to rail Cas into the bed until he was stuck on his knot, pumped full of Alpha come, but he needed to slow himself down. This was the angel’s first time, and Dean wasn’t going to ruin it by being reckless.

Climbing onto the bed, he ran a hand over Cas’ ass cheeks, squeezing gently, the reward of Cas’ soft moan making him smile. Slowly, he bent, spreading his angel’s ass with his fingers, flicking out his tongue to taste the sweet slick that leaked from him. The taste was overwhelming, sweet and salty, and Dean groaned, pushing his face closer to Cas’ hole as the angel fisted his hands in the pillows and cried out.

‘Gonna make you come, Omega,’ Dean muttered, pulling back only to plunge his tongue into Cas’ slick-soaked hole. The Omega shuddered and gasped, his walls fluttering around Dean’s tongue as the Alpha kept stroking and teasing him. His cock bobbed between his stomach and the bed, leaving a trail of precome on the sheets and his skin, and he wondered if it was possible to come untouched, with just his Alpha’s tongue in his ass.

‘My Alpha,’ Cas whined, without meaning too, and Dean’s head came up, a strange prideful look on his face. The angel didn’t seem to notice, and Dean growled, nipping at Cas’ ass and making him jump.

‘Damn right, I’m yours.’ The words were forceful and possessive, and he knew he couldn’t hold back any longer. ‘Fuck, Cas, I gotta knot you.’

Cas swallowed, nodding, gripping the pillows tightly. ‘Please, Alpha. Need your knot.’

Dean sucked in a shaky breath, fisting his cock as he straightened his back and lined himself up. The second the head of his cock brushed against the angel’s fluttering hole, Cas whimpered, and Dean had to hold back from slamming into him and taking him as hard as he could. He’d never been so affected by a wet, pliant body before, but then, he’d never loved anyone so wholly as he’d loved Castiel.

The thought made him pause, and he closed his eyes, feeling the barest touch of Castiel’s ass on the tip of his dick, the angel’s hips pressing backwards, his needy body craving what only an Alpha could give. What only  _ his _ Alpha could give.

‘Dean, please -’ Cas whined again. ‘I need it. I need you.’

Dean’s control snapped, and he pushed forward, inch by inch, savouring every little whimper and moan that the angel gave as he sank into his willing body. His cock stretched him out, and he was tighter than anything Dean had ever experience, and he felt his knot wanting to swell, like a teenager in rut. God, he didn’t want this to end so quickly.

Cas’ hips were still moving, drawing him closer and closer, and Dean grabbed him with his hands as he bottomed out, holding him still. ‘You gotta stop that. I’m gonna pop and I don’t want this to be over just yet.’

The angel nodded. ‘I’m sorry, I just - it feels so good.’ He was panting into the pillow, fingers clenching and unclenching in the material as Dean held his position. The hunter bit his lip, dropping his chin to his chest as he tried to control his body’s reaction to being so completely  _ one _ with his Omega. ‘Alpha,’ Cas whispered, and Dean nodded, evening out his breathing as he focused on what Cas needed.

‘I’ve got you,’ he replied, pulling out a little way and thrusting back in, Cas’ slick coating his cock, the Omega’s answering mewl everything he needed to hear. ‘Always got you, Cas.’ Dean kept moving, measuring his strokes, keeping them steady and slow, but hard enough for the slapping sound of his pelvis connecting with Cas’ ass to echo through the room. He let his head fall back as he relished the feel of his Omega wrapped around him, the tight wet heat dragging back and forth over his cock.

The air around them rippled, and Cas arched, black shimmering lines coating his back, and Dean watched as thick black wings unfurled, stretching outwards to either side of his body. ‘Shit, Cas, I -’

‘I know,’ the Omega panted. ‘I need...I need…’ Dean reached forward, running his fingers through the soft down of the angel’s wings, making him cry out, his head coming off of the pillow in ecstasy. His wings quivered and stretched out further, covering the bed from one side to the other and hanging off of the edge.

‘So fucking beautiful,’ Dean whispered, tugging gently at the feathers, and Cas’ entire body shuddered in response.

‘Need your knot, Alpha,’ Cas begged, and Dean groaned, knowing he couldn’t hold back from giving the angel exactly what he wanted. His thrusts increased, and Castiel’s whimpers mingled with Dean’s grunts as he began to fuck him in earnest, feeling the familiar tightening in his groin. ‘Dean… I’m… I’m…’ The angel’s speech trailed off into a jumble of words that Dean didn’t recognise, and he cried out in surprise as the Omega tensed underneath him, his hole clamping down on his Alpha cock as he came over the sheets. Cas gave a strangled yelp, his fingers going white as he clutched the sheets. 

Dean groaned as his knot started to swell, making his thrusts slower, and he bent double, his hands grabbing at Castiel’s wings as he slowly became lodged inside him, the thick width of his knot impaling the Omega and holding him fast. The coil in his belly snapped and he came hard, pumping rope after rope of hot come into the warmth of Cas’ body.

The Omega underneath him went lax, and his harsh pants dissolved into steady breathing as Dean stilled, almost slumped over him, his fingers stroking at the thick black feathers of Cas’ wings. Slowly, they curled back in, tucking tightly against his back as Dean pressed his forehead into him, looping his arms underneath his belly to hold him tight.

‘I’m gonna have to move,’ Dean muttered, not wanting to move in the slightest, but feeling his legs cramp up. ‘We’re gonna be here a while.’ Cas nodded into the pillow, and his wings curled further in, disappearing entirely as Dean eased the both of them onto their sides. He pulled Cas up close, nuzzling into his back.

‘You didn’t claim me,’ the angel murmured, his eyes closed as Dean rubbed his nose into his hairline.

‘There wasn’t much room with your wings in the way,’ he pointed out, smiling against his Omega’s skin. ‘I want to, though. Don’t think I don’t.’

Castiel nodded, keeping his eyes closed as he hummed contentedly. ‘Good. I want to be yours, Dean.’

‘What makes you think you weren’t already?’ The hunter replied, letting his own eyes fall shut. Sam may have been right, but he may have also been wrong. Either way, Dean wasn’t giving up his angel Omega without a fight.


End file.
